1. Field of the Invention
The present invention relates to a waveguide adapter able to generate a circularly polarized wave, this waveguide adapter enabling optimal generation of a circularly polarized wave signal for use in communication systems using circularly polarized wave signals and artificial satellite communication systems.
2. Description of the Related Art
A satellite communication system is installed in an artificial satellite for communication between the satellite orbiting in space and an earth station. To be installed in the artificial satellite, the satellite communication system entails features of low weight and a high degree of strength. Accordingly, it is necessary for the satellite communication system to achieve a maximally simplified configuration and small size.
In the meantime, although such a satellite communication system utilizes a circularly polarized wave signal for ease in transmission of signals to or from the ground, most general signal generators and antennas have characteristics of a linearly polarized wave. Therefore, there is a need for a special polarized wave conversion structure.
A high strength waveguide is widely used in a satellite communication system, to transmit a high output signal. Such a waveguide needs a conversion device (i.e. an adapter), which connects a transmission line of the waveguide and a transmission line of a satellite communication system to each other, so as to transmit a signal processed in the satellite communication system to, e.g., a horn antenna.
A communication system using a circularly polarized wave signal has advantages of excellent signal transmission characteristics with respect to the surrounding environment and separation of a left hand circularly polarized wave signal and a right hand circularly polarized wave signal and therefore, has been applied in many fields including satellite communication, mobile communication, radio frequency identification systems (RFID), and the like. With this tendency, there is a great demand for a circularly polarized wave generator and a waveguide adaptor.
However, due to the fact that the use of a circularly polarized wave generator and a waveguide adaptor are necessarily required in order to generate a circularly polarized wave, a conventional communication system using a circularly polarized wave signal disadvantageously entails an increased size and complex system configuration.